Caster glide



June 9, 1953 M. KRAMCSAK, JR

CASTER GLIDE Filed May 7, 1949 June 9, 1953 M. KRAMCSAK, JR

CASTER cum:

2 Sheets-Sheet 2 Filed May 7, 1949 17TH I k\\\ TTORNEYS Patented June 9, 1953 CASTER GLIDE Michael Kramcsak, Jr., Bridgeport, Conn, as-

signor to The Bassick Company, Bridgeport, Conn., a corporation of Connecticut Application May 7, 1949, Serial No. 92,053

12 Claims.

This invention relates to caster glides, and more particularly to those applicable to tubular metal furniture legs.

One of the objects of the invention is to provide an improved caster glide which is very readily applicable to an open-ended tubular leg, and which, after installation, will be securely held in place.

Another object is to provide a simple caster glide structure that is of minimum height, which is provided at its upper end with very effective means for engaging the furniture leg, so that, notwithstanding hard service, the glide will not be displaced or lost.

Another object is to provide an improved structure of this class in which noise and vibration affecting the base portion of the guide will not be transmitted to the leg.

In the accompanying drawings:

Fig. 1 is an enlarged vertical central section through a glide embodying my improvements, showing it applied to the lower end of the tubular Fig. 2. is a side elevation of the glide;

Fig. 3 is a top plan view;

Fig. 4 is a vertical section showing a modified form;

Fig. 5 is a top plan view of the article shown in Fig. 4; and

Figs. 6, 7, 8 and 9 are vertical sections showing additional modified forms.

In the glide illustrated in Figs. 1 to 3, inclusive, the structure is of character such that noises and vibration affecting the metal base, which is adapted to slide along the floor, will not be transmitted to the furniture leg, there being provided for this purpose cushioning or vibration-damping means in the form of a molded rubber plug, or a plug or body of rubberlike material. This plug is received in a metal base or shoe constituted in thisinstance by a sheet metal cup. The glide is provided with a stem rising from the base and adapted to enter the lower end of the tubular leg, which stem in this instance comprises a rivet. The rivet holds in place at the upper end of the stem a leg-engaging retaining member constituted by an umbrella-shaped part of resilient material, said part being held in place between the upper end of the rivet and a dome-shaped spacer member supported upon the above-mentioned rubber plug.

In the drawings the lower end portion of the hollow cylindrical furniture leg is indicated at ID, the metal base of the glide at I l, the rubber body or plug at l2, the rivet at l3, the dished or cup leg-engaging retainer at M, and the domeshaped spacer at [5. There is also shown at I6 a flat metal Washer interposed between the spacer I5 and the plug l2. This washer It in the operative position of the glide is resiliently supported upon the upper surface of the cushioning plug and underlies and engages the lower edge of the leg l0, as illustrated in Fig. 1. The glide is very tightly held in the assembled position by the biting engagement between the perip-hery of the retainer l4 and the inner cylindrical surface of the leg.

The base member H is constituted by a generally cup-shaped sheet metal member having a side wall which is curved and turned inwardly to provide eifective retaining means for the rubber plug I 2. The inturned edge of the base is indicated at H, and this is received in an annular groove [8 provided in the plug [2, preferably about midway of the height of the plug. The plug preferably has a height which is approximately twice the depth of the metal base, and the plug is molded so as to conform to the interior of the base, as shown in Fig. 1, and above the base the plug is extended laterally to provide the previously mentioned groove l8, and to provide a peripheral portion which overlies a portion of the metal base, although the upper portion of the plug in this form has a diameter somewhat less than the outside diameter of the base.

In the lower end of the plug I2 is a recess Hi allowing ample clearance depthwise for the flat shallow head, which in this form is provided upon the lower end of the rivet, this head being indicated at I9. Leading upwardly from the recess l8 in the plug is a plug bore 2i! in which the shank of the rivet is disposed. The spacer It? has a similar bore for the rivet shank, and the washer It has a perforation closely conformed to the rivet shank. The washer H5 in this form has an outside diameter approximately equal to that of the furniture leg,but the dome-shaped spacer l5 has a maximum outside diameter such that there is substantial clearance between it and the inner surface of the leg. The spacer 15 preferably but not necessarily has" the crossseotional'shape shown in Fig. 1, there being a short, substantially cylindrical, lower surface which extends from the dome-shaped surface to the bottom of the spacer.

The umbrella-shaped member 14 is held snugly in place between the outwardly curled or bent upper edge portion 2| of the rivet and the top of the dome-shaped spacer. The upper end of the rivet is provided with a flaring recess 22 which enables the rivet to be curled over to clinch the retainer. In the operative position shown in Fig. 1, the retainer is curved on an arc the radius of which is somewhat greater than the radius of the curve of the spacer, so that the retainer engages the spacer at the summit only.

The retainer normally has the umbrella shape or dome 'shape, and is "preferably made of steel which is very resilient so that upon distortion it tends to reassume the initial shape. The peripheral portion preferably has the contour shown in Fig. 3, in. which there are four squared-off portions that project beyond the periphery of the remainder of the member .and provide corners that bite into the metal of the tube. Anyiattempt to pull the glide out of the leg causes therretainer to flatten, which increases its diameter, and this makes the sharp square corners dig deeper into the metal of the tubing and brings the :remain ing portion of the retainer periphery into contact with the inner surfaceof the=tube soas to provide additional resistance to removal.

In the drawings, the squaredwff sections referred to are indicated at 23, these being ,provided at the ends'of diameters which areat right angles to each other. .Each of .these sections has a straight end edge of substantial length-and side edges which are at right angles to this edge. These squared-off sections are separatedby short notched portions 24 fromportions v25 which .have curved outer edges. The portions 25 are preferably somewhat wider than the portions 2.3, and the corners of the portions .23 project beyond the circle coinciding with the outer edges of the portions 25. The portions 25 are drawn into more intensive contact with-the tube interior when .pull is exerted upon the retainer when the latter is dug in at the corners f the portions 23.

The washer 16 is preferably madeof steel, and this acts to support the chair leg-and to spread the load over the surface of the cushioning member. The domed spacerserves to take side thrust and to protect the umbrella member from damage. The domed top of the spacer acts to support the umbrella during installation, and to allow for maximum flexibility-of grippingaction, and fit of the umbrellain the tubing-within commercial tolerances.

The head I9 of the rivet is of substantially greater diameter than the bore in the rubber plug, in order to prevent the rivet from being pulled through the rubber. The head l9 is'of shallow depth in comparison to the recess I8 and in the assembled position of the glide parts is tightly engaged with the rubber defining the ceiling of the recess I8 in order that there may be no metal-to-metal contact between thebase-and the rivet which would permit transmission of vibration to the rivet andthence to the furniture leg. The rivet head I9 is held in the position just indicated by the curling'over of the upper end of the rivet. By this construction, noise and chatter cannot be carried upwardly into the leg of the chair or other article.

The application of the glide to the furniture is-extremely simple. The glide is held in place at the bottom of the leg, and is driven home by a light blow of a mallet. .After installation the glide can be removed by lanauthorized mechanic or maintenance man using proper tools, disassembly being facilitated by the fact that the curled-over upper end of the rivet will permit break away when the :glide must be removed for replacement, but on the other hand the glide cannot be removed without tools, and this iS. a

distinct advantage where the furniture is used in schools and other institutions. The fact that the furniture can be moved over the floor without noise and chatter is, of course, a very important advantage.

The improved article also has the advantage that its over-all height is brought to a minimum, it being'unnecessary to e-xtend the glide into the furniture .leg to any considerable extent.

In this form there is very effective vibration rdamping owing to the fact that the rivet is out of contact with the metal base, and the metal base 'effectively separated from the chair leg by a substantial underlying body of cushioning material. In this construction the part which connectsthe baseto'the umbrella is not only a part separate from the base, but separate from the member lbwhich directly underlies and supports the 'umbrella, the member l5 being part of a composite retainer-supporting structure.

.In the form shown in Figs. 4 and 5, the glide comprises a base, a stem or post, and a mounting structure for the umbrella, all made integral with each other. The base is a solid base formed as a head on a cylindrical shank or stem, and at the upper part of this shank or stem-the mounting for the umbrella isprovided, said umbrella in this particular instance being staked in place on areducedneck portion of the stem. Here the base .of the glide is indicatedat 26, the stem or shank at 2'1, and the umbrella at T28. The umbrella is staked in place on a collar or neck portion .29 of reduced diameter adjacent the upper end of the stem, and the staking of the upper endof the stem against the umbrella produces the laterally extending clinching head 30. Immediately beneath the collar portion or neck portion 29, the stem is sloped or beveled to provide a portion 3| which is divergent from the umbrella which overlies it, and corresponds to the divergent part which is provided upon the previously described spacer member [5,although the portion 31 is in this instance shown as being on an incline rather than on a curve. The stem structure is of substantially greater diameter below the umbrella than it is in the portion surrounded by the umbrella. The base 26 has a flat polished lower surface to slide on the floor, and it has an upwardly curved side surface indicated at 32 extending upwardly to a flat surface 33 which is the upper surface of the base. The stem or shank 21 isintegrally connected with the base-at the center of this upper surface, on a suitable fillet.

Around the stem on the surface 33 is supported a molded cushion 34 constituted by an annular plug of rubber or rubberlike material. On top of this plug is supported a stepped metal washer 35, and on the peripheral portion of this metal Washer, the lower edge of the furniture leg is supported. The arrangement is such that the furniture leg is cushioned from vibrations moving upwardly from the base 26 or laterally from the body of the stem 21. To achieve this, in the particular form shown, the leg rests on the peripheral part of the washer, which rests on a rubber portion between this part of the washer and the base, and the rubber cushion has a radially inner part that is continued upwardly so as to provide a sleeve portion disposed between the stem and the inner edge of the Washer. The washer has a peripheral leg-supporting portion 36, and an upwardly offset portion 3'! between which-and the stem 21 a sleeve-like part 38 on the rubber plug is interposed. The parts 36 and 31 of the washer are joined by an inwardly and upwardly sloping part 39. The rubber of the plug preferably conforms fully to the washer part 36, and partially to the washer part 39, as shown in the drawings, and the construction is such that the underlying rubber part, which conforms to the lateral surface of the stem and is precisely centered thereby, in turn centers in a precise manner the washer which is to engage the lower edge of the metal tubing.

In this form the contour of the retainer at the peripheral part is somewhat different from that disclosed in Fig. 3, but there are two diametrically located squared-off projecting portions adapted to dig into the surface of the tubing in the manner previously described. These projecting portions are indicated at 40. Instead of being curved on the umbrella arc, as in the first form, these projections are inclined, as shown. In place of the other pair of squared-off projections, a pair of inclined pointed projections 4! are used in this instance. The peripheral line or circle of what may be termed the body part of the umbrella is provided by the curved edges of portions 42, which correspond generally to the portions 25 of Fig. 3. The squared-off projections 40 are on one diameter and the projections 4| are on a diameter at right angles thereto, and the portions 42 are, as before, in the respective quadrants. The projections M are V-shaped projections, having their sides substantially at right angles to each other, and at their points or apices they dig into the surface of the tubing for anchoring purposes. Also, in this particular instance narrower V-shaped inclined projections 43 are located adjacent the sides of the projections 40 extending outwardly and downwardly beyond the circumference of the body portion of the urn brella.

This form of glide provides a very strong and rugged article, which will withstand severe service conditions, and, as before, the furniture leg is isolated from vibrations imparted to the glide structure by reason of the contact of the glide with the floor. -As before, a body of rubber prevents transmission of vibrations upwardly from the base to the leg, but, inasmuch as the stem is integral with the base so as to be in a vibrationtransmitting relation thereto, it is considered necessary for best results to place a cushioning part between the body portion of the stem and the legsupporting washer.

The form shown in Fig. 6 is similar to that of Figs. 4 and 5, with the exception that the rubber body placed on top of the base is a flat rubber washer 44 which supports the stepped metal washer 45 by underlying and engaging its peripheral flange 46. The upper part 41 of this metal washer is spaced upwardly from the upper surface of the rubber washer, and the lateral cushioning of the upper part of the metal washer is omitted. The umbrella is the same as in Fig. 6.

Fig. 7 shows a simpler form of glide in which the leg-engaging washer and its underlying support are omitted. In this case the base 48 has an upper surface 49 receiving directly the lower end of the tube, and the tube is centered by a centering boss or shoulder 50 rising from the base and integral with the base and with the stem The centering boss 50 has a body which is of .an external diameter corresponding to the inner diameter of the tube, this part of the boss being cylindrical. Immediately above this cylindrical part and at the top, the boss is chamfered in a narrow area, preferably at 45, as shown at 52,

the purpose of this being to facilitate the insertion of the glide into the furniture leg. The umbrella is the same as in Figs. 5 and 6.

The form shown in Fig. 8 is the same as that shown in Fig. '7, except for the fact that the umbrella, instead of being held in place by staking, is held in place by a hollow rivet which is curled over. In this case the upper end of the stem has a flaring recess 53, and the stem is bent or curled over to provide a clinching flange 54.

The form of glide shown in Fig. 9 is similar to that disclosed in Fig. l, but in this instance the use of a leg-supporting metal washer and a separate spacer piece is dispensed with. Instead of employing these separate parts, I employ a member 55 which can be conveniently made of pressed powdered metal, and which presents a dome-like spacer having an integral laterally extending base flange 56 that is adapted to engage the lower edge of the furniture leg.

It will be seen that the invention provides an improved caster glide which is very readily applicable to tubular furniture, and which, after installation, will be effectively held in place notwithstanding hard usage. It is unnecessary to provide special means for distorting or spreading the cupped or dished leg-engaging retaining member to cause it to dig intothe surface of the tube. The structure lends itself to easy introduction of the glide into the leg, owing to the fact that the round concavo-convex retaining member or umbrella is in general of an upwardly pointed formation; and when it comes to downward movement of the glide structure, which is necessary in displacing it with respect to the leg, any such downward movement in and of itself occasions the digging in of the peripheral part of the retainer, which in turn causes a flattening and increase of diameter of the retainer, and the more the retainer is flattened, the more tightly will it engage the leg to prevent downward displacement. This action will take place in and of itself at any time when there is a tendency of the glide to be displaced downwardly. It is also of manifest advantage to be able to prevent the transmission of noise and chatter to the furniture legs. The construction also has a number of additional advantages, as has been pointed out above.

In all of the forms herein shown, the umbrella is a relatively shallow member perforated at the top and having its highest part adjacent the edge of the perforation, and, as this member is shallow, its radius of curvature is relatively long. In the form shown in Fig. l, the center of the arc of the umbrella is well below the lower edge of the furniture leg and at the lower part of the rivet. In the form shown in Fig. 4, the center of the arc is not only below the edge of the furniture leg, but below the level of the glide in a location adjacent the fioor line, although obviously there may be variation to meet different conditions. It will be noted that in both forms of umbrella herein disclosed, namely that of Fig. 3 and that of Fig. 5, the squared-off anchoring projections are separated from the parts having the body-defining curved edges drawn from the center of the umbrella, by intervening notches which extend inwardly past the curved edges.

Several different embodiments of the invention are herein disclosed, but various additional modifications and changes in the details may be made without departing from the principles of the invention or the scope of the claims.

I do not claim specifically herein the forms of the glide shown in Figs. 4 5308,2inc1uSiVe, as :these are claimed in :my divisional application Serial No. 135,409,:filed December 28,1949.

What I claim is:

1. In a caster glidefor applicationto the lower open end of a hollow .tc-ylindrical "furniture leg, a base in the form of a cupped metal shoe having an inturned upper edge, a cushion retained in said shoe by said edge :and extending upwardly beyond the shoe, an element supported on the upper face of :said cushionadapted to engage'the lower edge of the furniture leg to support the same,.a spacer above said element adapted to be disposed within the :lower part of the leg and having at the upper part a rounded supporting dome of substantial diameter, a retainer in the form of a shallow umbrella of resilient material supported'on the dome of said spacer in-diverging relationship thereto and adapted to have peripheral anchoring engagement with the inner surface of the leg, and a fastening 'member'for the glide assembly extending through registering apertures in the cushion, element, spacer and retainer and having-a laterally expanded upperend between which and the summit of said spacer saidretainer is held.

2. "In a caster-glide for application to the lower open end of a hollow'cylindrical furniture leg, a base in the form-'ofza cuppedmetal shoeya cushion within the shoe extending upwardly beyond theshoe and adapted to support the lower .edgeof the furniture log, a dome-shaped spacer above said cushion adapted to be disposed within the lower part of the leg, a retainer in the form-of an umbrella of resilient material supported on the upper end of said spacer and-of greater radius of curvature than said spacer so that the under surface of the umbrella and the upper surface of the spacer diverge from each other laterally and outwardly and adapted to have peripheral anchoring engagement with the inner surface of the leg, and a fastening member for the glide assembly extendin through registering apertures in the cushion, spacer and retainer having .an upper end between which and the summit of said spacer said retainer is clinched.

3. A caster glide-as defined in claim ,2, in which the fastening member is constituted by a rivet having a hollow upper end curled over the retainer.

4. In a casterglide for application to the lower open end of a hollow cylindrical furniture leg, a base in the form of a cupped metal shoe having an inturned upper edge, a cushion retained in said shoe and extending :upwardly beyond the shoe, an element supported on said cushion made in one piece and comprising a lower portion adapted to underlie the lower edge of the leg and an upstanding portion integral therewith of solid or blocklike formation presenting a domeshaped top, a retainer in the form of a shallow umbrella supported on and against said domeshaped top and of greater radius of curvature than said dome-shaped top and adapted to engage the inner surface of the leg, and a fastening member extending through registering "apertures in the cushion, element and retainer and securing them tightly together in assembled relationship.

5. A caster glide for application to the lower open end of a tubular furniture leg, comprising a base, an umbrella-shaped retainer adapted to engage the inner surface of the leg,-a stem on which said retainer is mounted adjacent the upper end of said stem saidretainer sloping outwardly :and downwardly from said stem and being tightly held between the upper end of said stem and an underlying part that diverges .outwardly and downwardly from the middle 'part of the retainer, and cushion means for supporting the leg from said base and mounting said stem from said base in vibration-damping relationship thereto.

6. A caster glide comprising a retainer adapted to engage the inner surface of a tubular leg and in the form of a shallow inverted cup, a spacer element presenting a solid dome immediately below said retainer supporting from below the middle portion of the retainer and whose surface diverges outwardly and downwardly from the under surface of the retainer at said middle portion, a cupped base, an interior cushion member supported in said base having an upwardly extended portion serving to support the lower end of the leg and the lower end of said spacer element, said cushion member, spacer element, and retainer having registering holes, and a fastener passing through said holes and interconnecting said parts.

'7. A caster glide as defined in claim 6, in which said fastener is constituted by a rivet having a head at the lower end and deformed by lateral expansion at the upper end.

-8. A caster glide as defined in claim 6, in which the solid dome of said spacer element has an integral outstanding foot portion adapted to underlie the lower edge of the leg.

9. In a'caster glide for application to the lower open end of a hollow cylindrical furniture leg, a base in the form of a cupped metal shoe having an inturned upper edge, a cushion retained in said shoe and having its upper surface at least as high as the top of the shoe, an element in the form of a block supported on top of the cushion and ofa diameter at its lower endapproximating the internal diameter of the furniture leg, said element shaped at its upper part to provide a gradually rounded dome and acting as a spacer between the base portion of the glide and an upper retainer, an upper retainer for the glide in the form of a shallow umbrella curved outwardly and downwardly from its summit resting on said spacer element at the summit of the spacer element and at the summitof the-retainer and diverging with respect to the upper surface of the spacer element and adapted to engage the inner surface of the leg, and a fastening member extending through registering holes in the cushion, spacingv element and retainer and holding them tightly together in assembled relationship.

10. A castor glide comprising a cup-shaped base, a dished resilient retainer in the form of a shallow umbrella adapted to engage the inner surface of a tubular leg, a cushion member adapted to support the lower end of the leg and extending downwardly into said base, and a fastener and spacer structure rigidly supporting said retainer at the middle portion only of the retainer at a predetermined height above said cushion member including a spacer member supported from the cushion member and presenting at the upper part a rounded dome the curve of which is of less radius than that of said retainer, the summit portion of the retainer being substantially in contact with the summit of the dome and the retainer diverging from the dome summit in a lateral and outward direction.

'11. In a caster glide for application to the lower open end of a hollow cylindrical furniture 1eg, a base in the form of a cupped metal shoe having an inturned upper edge, a cushion retained in said shoe by said edge and extending upwardly beyond the shoe, an element supported on the upper face of said cushion having a flange adapted to engage the lower edge of the furniture leg to support the same, said element having integral with said flange a spacing member having an upwardly extending part presentin a rounded supporting dome of a diameter approximating that of the cavity in the leg, a retainer in the form of a shallow umbrella of resilient material supported at its highest part on theftop of the dome in diverging relationship to the upper surface of the dome and having peripheral projections for engaging the inner surface ofIthe leg, and a fastening member for the assembly extending through registering holes in the cushion, spacing member and retainer.

12. In a caster glide, a cupped round base, a cushion within and extending upwardly from said base, a spacer having a round lower flange or foot supported on the upper peripheral area of said cushion and having a part integral with said 10 foot presenting an upper gradually rounded dome, a shallow umbrella retainer supported at its highest part on the upper end of said dome and diverging from the dome surface, and means including an upright shank-like member passing through the cushion, spacer and retainer for holding them tightly in assembled relationship.

MICHAEL KRAMCSAK, JR. 

